The casino billboards lining America's roadways tantalize with the lure of riches. "Easy Street. It's Only a Play Away," screams one in Arizona. "$7.1 Million Every Day. We're a Payout Machine," reads another.

But how often do gamblers really win? What are the chances that a gambler will win on a single day or over a longer period? Don't bother to ask the casinos. Although they gather vast quantities of data about their customers for marketing purposes, including win and loss tallies for many regulars, casinos keep such information a closely-guarded secret.

Now, thanks to an unprecedented trove of public data detailing the behavior of thousands of Internet gamblers over a two-year period, The Wall Street Journal can provide some answers.

On any given day, the chances of emerging a winner aren't too bad—the gamblers won money on 30% of the days they wagered. But continuing to gamble is a bad bet. Just 11% of players ended up in the black over the full period, and most of those pocketed less than $150.

The skew was even more pronounced when it came to heavy gamblers. Of the top 10% of bettors—those placing the largest number of total wagers over the two years—about 95% ended up losing money, some dropping tens of thousands of dollars. Big losers of more than $5,000 among these heavy gamblers outnumbered big winners by a staggering 128 to 1.

The analysis comes from a database containing anonymous records of 4,222 Internet gamblers who wagered on at least four days on casino-style games of chance such as blackjack, roulette and slots. They played between 2005 and 2007 on websites run by a major European online gambling concern, Bwin.Party Digital Entertainment PLC.

Bwin made the information available to gambling-addiction researchers affiliated with Harvard Medical School, who posted much of the data on the Internet. Bwin says there's no reason to believe a more current sample of customers would show significant differences.

Although the online Bwin customers differed in some ways from those typically found in a U.S. casino, their win and loss patterns should be roughly similar because the games are similar, said Robert Hannum, a University of Denver specialist in gambling mathematics.

To check, the Journal asked Puneet Manchanda of the University of Michigan and Hee Mok Park of the University of Connecticut to analyze a private gambling database to which they have access, detailing two years of play by 18,000 holders of loyalty cards at a Native American casino in the northwestern U.S.

The researchers found similar patterns: Only 13.5% of gamblers ended up winning, versus 11% among Bwin customers, and the ratios of big losers to big winners were similarly large.

The Bwin data also offer a peek at the economics of the casino industry that only insiders normally glimpse. Among the findings is an extreme reliance on revenue from a small number of gamblers.

Of the 4,222 casino customers, just 2.8%—or 119 big losers—provided half of the casino's take, and 10.7% provided 80% of the take.

Such revenue concentration long has been quietly acknowledged in the casino industry, but the Bwin information may be the first to show it with hard public data.

The issue is a sensitive one in the industry because gambling critics often cite revenue concentration as one sign that casinos exploit gambling addicts, which executives dispute.

"Politically, we don't want to talk about it being more concentrated than other industries," said Andrew Klebanow, a marketing specialist who has consulted for dozens of casinos. He said the Bwin results are in line with his own estimates, based on confidential casino data, that many U.S. casinos get about 90% of their revenue from 10% of customers. (The two professors found that 9.3% of the gamblers at the Native American casino produced 80% of the group's revenue.)

Jim Kilby, a former professor who has written three books on casino management, said the scant number of winners among Bwin customers was surprising even to him, and should be educational to gamblers.

Although gamblers know the house has an edge, he said, "the average person doesn't understand the math" of the multiplier effect: "Casino games are nibbling machines, and the more nibbles you have, the bigger your losses."

The Bwin data clearly show that. The lightest gamblers—the 10% of customers who placed the fewest wagers over the two years—also had the highest winning percentage. About 17% of them ended up in the black—tough odds but still better than the dismal 5.4% winning percentage of the heaviest gamblers.

Among the whole group of 4,222 gamblers, just seven won more than $5,000 (€3,698) over the two years, while 217 lost more than $5,000. That's a 31-1 ratio of big losers to big winners.

Gambler No. 1357078, a Swiss man who was 56 years old when he opened his account, was a classic heavy gambler. He played an average of three days a week, typically placing more than 1,000 bets per day and averaging $9 per bet. He lost on 84% of the days he gambled, and over the two years gambled away more than $110,000.

Unless they cheat, about the only way gamblers can win at games of chance is to get lucky and then stop gambling.

That's how No. 1381787 emerged as the biggest overall winner. A 56-year-old Slovenian man, he typically placed only a few modest bets per day. Then he struck gold, twice winning more than $14,000 within 10 days. After suffering a partial setback, he stopped playing on the Bwin site, netting about $22,000.

A separate Bwin database covers poker play. Poker is partly a game of skill, and the outcomes reflect that. About one-third of the poker players classified as "most involved" by the Harvard researchers ended up winning money over time, while just 10% of the rest ended up in the black.

Despite the slim chance of winning shown by its own data, Bwin has been enticing gamblers on one of its sites to "play for huge rewards on classic casino games," adding "the odds are certainly in your favor!"

Joachim Haeusler, Bwin's responsible gaming manager, said the company provides entertainment and people shouldn't gamble "based on the idea to get rich, because they won't."

How often do gamblers win? It is a very difficult question and we cant answer it. I think so because there are people who can win a lot of money and there are people who can win 0. So, only luck can give you your win. And that is why risky players gamble without any hesitations and only some of them know their limits. As for me, I prefer slot games like Book of ra and sizzling Hot. However, I play them for fun only. I dont need extra money. I play for having fun. There are a lot of sites with free software. I can share one page with a lot of free slots - http://webslotcasino.com/free_online_slots . I just know that slots are free and players test many slots from different providers here.

One thing that was not mentioned in the article is the role of "promo codes" or bonus offers. If a player takes full advantage of these and shops around to several different casinos he can improve his odds of winning. If you are thinking of playing here is a place to get started.http://lasvegas.im/sports-books/sports-book-bonus/

When governments make vices legal you’re left with no other choice but to put regulations into the laws that govern these vices. When it comes to the gaming industry VICE/SCAM I know my safeguards things like No 24/7 Gambling, No Free Booze, No Smoking, No Check Cashing, No Interest Free Credit, No Free Play, No Comps, making casino operators send Casino Monthly Statements to those enrolled in casino reward card programs along with making casino employees intervene when their patrons are gambling excessively will stop the ‘BREEDING’ of compulsive casino gambling degenerates who will become criminals. These regulations will also make it an even playing field for business owners that are within a 10 to 20 mile radius of casinos, especially those who have liquor, food, and entertainment licensees.

To learn more about Casino Monthly Statements and this ‘VICE/SCAM’ know today as ‘GAMING’ go on line and Google-up Bill Kearney on casino gambling.

Gamblers would do a lot better if they could own the casino or house the way mutually owned insurance companies theoretically are supposed to work. That way the casino could take much smaller fee per wager and refund earnings to their best customers. If I were to buy a Vegas Casino I would convert it to a club with a Costco like annual fee to join after gamblers purchased enough shares in the company to become owner members then operate for members only and maybe fee daily visitors who would pay something up front for the much better odds. The whole idea is if it is a game like golf as casinos want us to think it is then participation in the whole experience of the casino might be a lot more fun and cost less over time. Things could realty go wrong with this idea if it became the next time share...OH NO>

The old lady hauls about 1400/1500 a month out our local casino. She is way to smart to gamble there, she works there. the paycheck is always good, great benefits, and discounts on all the side stuff like the restaurants and shows. If she wants to bet on something, We someplace fun, like the horse track.

This sounds a lot like the Pareto Principle, where 20% of the participants account for 80% of what is happening (Google it!). Interesting that the same principle should affect gambling, and be even more skewed, because this is where you would think that the Law of Averages would make things much more uniform?

Sounds like the Internet casinos are pretty greedy. Probably due to not being able to hear other customers complain like in a real casino. I had a math professor who consulted in Vegas to make extra money. She didn't go to casinos to gamble. Maybe lucky in the beginning but assuredly sad in the end (gamblers who go chronic). There was a time when society and government did not allow commercial gambling since the house always wins (10% to 15% of every dollar gambled is kept; reduces complaining). Now the state promotes it.

Our government(s) run the gambling operations with the worse odds of all, the lottery. You won't find statistics on this becuase there is also an 80/20% rule in this scam. 80% of the money is brought in from 20% of the poor who take everything they have week after week (many cases a government check) down to the local store and wagger all they have on odds that are 1 in millions.

I do enjoy going to the casinos occasionally here in Southern CA, which means Indian Casinos. I live in LA, and most of the good ones are 90 minutes or so away, and you really don't have to gamble much for them to start sending you the offers for free hotel stays, free meals, etc - as well as promotions like "free play" or some even give you cash every time you stop by. Obviously, the assumption - and reality, otherwise they wouldn't be in business - is that if you come and stay a couple nights, you'll go through the free offers, eat your free food, see your free shows, but still end up dropping more money than the cost of everything they gave you for free to entice you to come gamble there. I'm careful to set limits as to what I will spend, and sometimes I just swing by a few of them (there are over a dozen nice casino / "resort and spas" within 2 hrs of LA), the ones that have the most generous offers and seem to have the "loosest" slots (of course, since the Indian casinos - unlike the non-Indian casinos in most states - are not required to disclose anything as to odds and payout %'s, etc - the only way you can "know" which ones have looser slots is based on your own experience, and also the ones that are on the tighter side aren't crowded, even on weekends, when most of them are very crowded) and/or table games that I like, use their free offers, and move on to the next casino. If I generate winnings from "their money", I might use some of that to gamble a little more, but try to walk away with at least close to the amount they gave me for "free". As someone mentioned, the tricky part is when you've driven a couple hours, and you're staying in their hotel, and you've had a good win, and you know you should maybe use a very small % of it to keep gambling, or - better yet - "take the money and run"! But you drove 2 hours and you're here to have fun! Nope, don't give it all back - find something else to do, either at the casino/resort, or nearby - most of ours are in or around Palm Springs and San Diego. And of course there's the opposite scenario, where you have really bad luck and quickly blow through the amount you set as the max you'll gamble, and there's the temptation to "up your max". But I'm careful to not do that--just enjoy the facilities, pool, eat your free food and stop gambling - trust me, they'll still keep sending you offers. Sometimes I wonder if it would be easier if you were a local... If I won big and lived 15 minutes away, seems like it would be easier to say OK I'm out of here and run with the money. Same goes with quickly blowing through your max. Whereas I think, I drove all the way here and have a room for two nights, and might not be back for a few weeks, so.. A local can say I'm going home, and I can always come back whenever I want. I certainly don't plan on moving to live closer to casinos, and I'm pretty sure it's not a good thing to live someplace like PS or SD with a half dozen casinos a few minutes away (I would have to think there are far more gambling addicts with multiple casinos so close), but sometimes I think it would be easier to say "stop" (good or bad) if I hadn't driven so far.. I haven't been to Vegas in years, but pretty much everyone says the odds / payouts there are noticeably much worse (on slots) than at the Indian casinos. Nearly everyone reports losing all their money in Vegas, whereas you can win at least a decent % of the time at the Indian casinos. Obviously in the long term, odds are you'll lose both places, but I think in Vegas, the state takes a big chunk; the casinos are bigger / more expensive - the CA casinos are nice (most of them, avoid the ones that aren't!) but not Vegas; and whereas Vegas draws millions of people every year based on the whole "Vegas experience" (bigger casinos, shows, nightlife, the party atmosphere) the Indian casinos are trying to make Southern Californians stay here to gamble instead of going to Vegas.

"Of the 4,222 casino customers, just 2.8%—or 119 big losers—provided half of the casino's take, and 10.7% provided 80% of the take."

In the IRS casino, the top 2 percent provide just under 40 percent of house receipts, and the top 10 percent provide 70 percent of house receipts. (The top 25 percent provide over 85 percent.)

Could it be that both the casinos and the IRS have figured out just how much they can plunder from their "customers" without them abandoning the games?

This may in fact be part of the reason raising taxes results in lower receipts. When the "customers" are being taken for all they are willing to tolerate losing, increase the take and increasing numbers quit playing.

It would be much more revealing to see gambling results by the game played. The results of various games (poker, Keno, roulette, slot machines) are likely very different. Additionally, so are the gamblers that choose various games.

I go into Casinos and gamble very seldom, but when I do its for entertainment. Being careful you can spend between $50 and $100 for about 5 hours of entertainment, about the same price as a round of golf or theater tickets.

There are two parts to successful gambling; knowing the odds of the game you are playing and thus minimizing the House's edge, and money management (knowing when to walk away from the table, whether up or down.

Played properly, craps has the best odds of all house games, but there are numerous sucker bets on the table, and that is where the house makes it's money, because those bets are always there. By playing the pass and come lines exclusively and laying odds on all bets, I can play for 5 hours and only be up or down 2 or 3 times my initial stake, given no extended hot or cold streaks of the dice. Of course, you rarely strike it big playing that way, but also do not lose big.

As mentioned before, poker is a different animal. Over the long haul, good players win far more than they lose. And in Vegas, the locals take money from people who watch poker on TV and think they know how to play poker.

If you're going to gamble, and you want the best odds of walking out a winner, place a few bigger wagers instead of a lot of smaller ones. Think about coin flips. You can beat the odds on a small series of coin flips (perhaps getting four heads in a row), but if you flip the coin 100 times, the number of heads will be a lot closer to 50%. And since casino games are stacked in favor of the house, average (the equivalent of getting heads half the time) will make you a loser. Over the long haul, over many trips to the casino, you'll end up a loser even making a few big bets per trip. But nobody should be going to these places multiple days a week. If you do it my way, and only go occasionally, you will have a significant number of winning sessions and be able to honestly call it entertainment.

The biggest problem is that making a few bets isn't very good at killing time, and perhaps doesn't provide the escape that problem gamblers seek.

Poker is different from all the other games. The higher the stakes, the better the opponents. A semi-competent poker player can grind out wins at low-limit tables in spite of the fact that the rake (house cut of every pot) is proportionally bigger. But a lot of people don't find much thrill in grinding out $40 or $60 winning sessions over a few hours of poker.

In general, if the casino is mailing you free slot play offers that just seem a bit too generous, you probably want to stay away from the places entirely.

Poker is the only casino game with even odds. In every other game, the house has the advantage. This is why there are countless Poker competitions on TV, but no "Celebrity Blackjack" or Roulette, or any other Casino game. No one can beat the house! The idea that's possible is the great illusion of gambling, because a built-in statistical advantage can never be defeated.

I don't think many people understand what "the house has the advantage" means. Those who do understand it, never play casino games. They understand that to play is simply foolish. The rest think there is some force called Luck or some trick to overcome the odds. Know anyone who has?

If only people understood the law of probability! I suggest Scott Adams' book (free online) "God's Debris." It changed my life.

I was a crapshooter for years and never left a casino a loser. The casinos shut me off, however, so I was forced to quit. Incidentally, the reason I was forced to play craps is because the casinos would bar me from playing blackjack.

I object. Betting on horses can be profitable if you have the proper skills and discipline to spot a good deal. Granted, most people don'i have those skills, but it can be much closer to an investing activity than a gambling transaction. You can even own a horse much easier than you can own a casino.

"I was a crapshooter for years and never left a casino a loser. The casinos shut me off, however, so I was forced to quit. Incidentally, the reason I was forced to play craps is because the casinos would bar me from playing blackjack."

Holy cow. What a bs artist. Are you a lawyer? Use magnetic dice? Use your x-ray on the cards?

You can even own a horse much easier than you can own a casino.___________

Having owned horses (not even race horses), I can assure you that can be a rapid path to bankruptcy.

A while back, ATF seized a criminal's race horses and thought they would make a lot of money off of them. Two years and many, many thousands of dollars later out of their budget, they instituted a new policy. Don't ever, ever take possession of a horse.

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